The purpose of this Phase I clinical trial is to evaluate the new antitumor agent, bryostatin-1, which appears to exert its antitumor activity from the modulation of protein kinase C activity. The primary objectives are to evaluate the MTD of bryostatin-1 in combination with cisplatin for advanced malignancy and establish a recommended Phase II dose based on the MTD and to evaluate the dose-limiting toxicity in this group of patients. Preliminary data will be obtained on the enzymatic activity of protein kinase C and the expression of the oncogenes c-Fos and c-Jun prior to, and after treatment with bryostatin-1 in accessible tumor biopsies. Steady-state pharmacokinetics of bryostatin-1 in plasma and its effect on protein kinase C in PBMCs will be assessed. Objective tumor response will be examined.